Lens tube, optical device having the lens tube, and method for producing the lens tube

Abstract

A lens tube includes a standard member, a lens, a guide, and a pushing member. The standard member has a standard surface via which the standard member is to be mounted to a camera main body. The lens retainer retains at least one lens and is connected to the standard member movably along an optical axis of the at least one lens. The guide is provided facing the lens retainer in a radial direction of the at least one lens to guide the lens retainer along the optical axis. The pushing member pushes the lens retainer and the guide in opposite directions.

1. A lens tube comprising:
 a standard member having a standard surface via which the standard member is to be mounted to a camera main body; 
 a lens retainer which retains at least one lens and which is connected to the standard member movably along an optical axis of the at least one lens; 
 a guide provided facing the lens retainer in a radial direction of the at least one lens to guide the lens retainer along the optical axis; and 
 a pushing member configured to provide a pushing force extending along a substantially radial direction with respect to the optical axis to push the lens retainer and the guide in opposite directions substantially radially with respect to the optical axis. 
 
     
     
       2. The lens tube according to  claim 1 , further comprising:
 a driver configured to move the lens retainer along the optical axis. 
 
     
     
       3. The lens tube according to  claim 1 ,
 wherein the lens retainer has a first screw portion and the guide has a second screw portion, the first screw portion and the second screw portion being screwed together, and 
 wherein the pushing member generates the pushing force to separate the first screw portion and the second screw portion from each other. 
 
     
     
       4. The lens tube according to  claim 1 ,
 wherein the guide comprises a straight guide portion which is connected to the standard member and which is configured to guide the lens retainer along the optical axis, and 
 wherein the pushing member is supported by the lens retainer and presses the lens retainer to get away from the straight guide portion. 
 
     
     
       5. The lens tube according to  claim 4 , wherein the pushing member comprises a leaf spring provided between the lens retainer and the straight guide member. 
     
     
       6. The lens tube according to  claim 3 , wherein the pushing member comprises a leaf spring provided between the first screw portion and the second screw portion. 
     
     
       7. An optical device comprising:
 the lens tube according to  claim 1 . 
 
     
     
       8. A method for producing a lens tube, comprising:
 providing a standard member having a standard surface via which the standard member is to be mounted to a camera main body; 
 connecting a lens retainer to the standard member movably along an optical axis of at least one lens, the lens retainer retaining the at least one lens; 
 providing a guide facing the lens retainer in a radial direction of the at least one lens to guide the lens retainer along the optical axis; and 
 providing a pushing member to provide a pushing force extending along a substantially radial direction with respect to the optical axis to push the lens retainer and the guide in opposite directions substantially radially with respect to the optical axis. 
 
     
     
       9. The method according to  claim 8 , further comprising:
 providing a driver configured to move the lens retainer along the optical axis. 
 
     
     
       10. The method according to  claim 9 , wherein the driver is an ultrasonic motor. 
     
     
       11. The method according to  claim 8 , further comprising:
 providing the lens retainer with a first screw portion; and 
 providing the guide with a second screw portion, 
 wherein the first screw portion and the second screw portion are screwed together, and 
 wherein the pushing member generates the pushing force to separate the first screw portion and the second screw portion from each other. 
 
     
     
       12. The method according to  claim 11 , wherein the pushing member comprises a leaf spring provided between the first screw portion and the second screw portion. 
     
     
       13. The method according to  claim 8 ,
 wherein the guide comprises a straight guide portion which is connected to the standard member and which is configured to guide the lens retainer along the optical axis, and 
 wherein the pushing member is supported by the lens retainer and presses the lens retainer to get away from the straight guide portion. 
 
     
     
       14. The method according to  claim 13 , wherein the pushing member comprises a leaf spring provided between the lens retainer and the straight guide member. 
     
     
       15. The method according to  claim 8 , wherein the lens retainer includes a first surface extending in parallel to the optical axis, wherein said guide includes a second surface extending in parallel to the optical axis and facing the first surface, and wherein the pushing member is provided between the first surface and the second surface and is configured to push the first surface and the second surface in the opposite directions. 
     
     
       16. The lens tube according to  claim 2 , wherein the driver is an ultrasonic motor. 
     
     
       17. The lens tube according to  claim 1 , wherein the lens retainer includes a first surface extending in parallel to the optical axis, wherein said guide includes a second surface extending in parallel to the optical axis and facing the first surface, and wherein the pushing member is provided between the first surface and the second surface and is configured to push the first surface and the second surface in the opposite directions.